Imaging findings in hippocampal sclerosis: correlation with pathology

We evaluated the ability of preoperative radiologic imaging to detect hippocampal sclerosis in 31 patients who underwent surgery for intractable epilepsy. Hippocampal sclerosis is commonly associated with surgically treatable temporal lobe epilepsy. It is pathologically described as neuronal cell loss with associated gliosis in the hippocampus. While previous reports have correlated imaging results with clinical or qualitative histologic findings, this study used quantitative pathologic criteria (neuronal cell density) to diagnosis hippocampal sclerosis. We focused our study on the 11 patients with cryptogenic temporal lobe epilepsy. Of these, nine had hippocampal sclerosis by pathologic criteria. MR findings included unilateral hippocampal atrophy, an increased signal in the hippocampus on long TR scans, and atrophy in the adjacent white matter and temporal lobe. Hippocampal atrophy was most frequently seen in the red nucleus plane on coronal scans, corresponding to the body of the hippocampus. We also compared hippocampal size on MR with neuronal density in surgical specimens of the 11 patients with cryptogenic temporal lobe epilepsy. A statistically significant correlation was found between MR size and neuronal density in CA3 and CA4 of the cornu ammonis and the granular cell layer of the hippocampus. Since temporal lobectomy eliminated seizures in seven of nine patients with hippocampal sclerosis, preoperative diagnosis by MR has important therapeutic consequences.     

Changes in bone mineral density in men starting androgen deprivation therapy and the protective role of vitamin D

Summary

Androgen deprivation therapy in 80 men was associated with declines in bone mineral density (BMD), which were greatest in the first year, and in the lumbar spine compared to controls. Vitamin D use was associated with improved BMD in the lumbar spine and in the first year.

Introduction

Decreased BMD is a common side effect of androgen deprivation therapy (ADT), leading to increased risk of fractures. Although loss of BMD appears to be greatest within the first year of starting ADT, there are few long-term studies of change in BMD, and risk factors for bone loss are not well-characterized.

Methods

Men aged 50+ with nonmetastatic prostate cancer starting continuous ADT were enrolled in a prospective longitudinal study. BMD was determined by dual-energy x-ray absorptiometry at baseline and yearly for 3 years. Matched controls were men with prostate cancer not receiving ADT. Multivariable regression analysis examined predictors of BMD loss.

Results

Eighty ADT users and 80 controls were enrolled (mean age 69 years); 52.5 % had osteopenia and 8.1 % had osteoporosis at baseline. After 1 year, in adjusted models, ADT was associated with significant losses in lumbar spine BMD compared to controls (?2.57 %, p?=?0.006), with a trend towards greater declines at the total hip (p?=?0.09). BMD changes in years 2 and 3 were much smaller and not statistically different from controls. Use of vitamin D but not calcium was associated with improved BMD in the lumbar spine in year 1 (+6.19 %, p?<?0.001) with smaller nonsignificant increases at other sites (+0.86 % femoral neck, +0.86 % total hip, p?>?0.10) primarily in the first year.

Conclusions

Loss of BMD associated with ADT is greatest at the lumbar spine and in the first year. Vitamin D but not calcium may be protective particularly in the first year of ADT use.     

Digital subtraction in gadolinium-enhanced MR imaging of the brain: a method to reduce contrast dosage

The aim of the study was to investigate the feasibility of using digital subtraction in contrast-enhanced MR imaging of the brain to reduce the MR contrast dosage without jeopardizing patient care. Fifty-two patients with intracranial lesions, either intra-axial or extra-axial, detected by computerized tomography were selected for contrast-enhanced MR imaging with half-dose and full-dose of gadopentetate dimeglumine. The half-dose unsubtracted, full-dose unsubtracted, and half-dose subtracted MR images were visually assessed by counting the number of enhancing brain lesions in the images and quantitatively analyzed by computing their lesion contrast-to-background ratios (CBR). The visual conspicuity of the half-dose subtracted MR images was comparable to that of the full-dose unsubtracted MR images ( p>0.05), whereas the CBR of the half-dose subtracted images was approximately two to three times higher than that of the full-dose unsubtracted images. The half-dose subtracted T1-weighted spin-echo images might be able to replace the conventional standard-dose T1-weighted spin-echo images in MR imaging of the brain.     

Epidemiology of venous thromboembolism in a Chinese population

BACKGROUND: Deep vein thrombosis (DVT) is uncommon in Asians and routine thromboprophylaxis for surgery is controversial. Despite recent reports of higher incidences in some Asian countries, population-based data are lacking. METHODS: Information from 2000 to 2001 was retrieved from a centralized computer public healthcare database serving an ethnic Chinese population of 6.7 million. The incidence, demographics and hospital mortality rates of DVT and pulmonary embolism (PE) were obtained, and analysed for different surgical categories. RESULTS: The overall annual incidences of DVT and PE were 17.1 and 3.9 per 100000 population respectively. Venous thromboembolic disease was more common with increasing age in both sexes. The annual age-specific incidences of DVT and PE were 81.1 and 18.6 per 100000 for those aged 65 years and over. Hospital mortality rates associated with DVT and PE were 7.3 and 23.8 per cent respectively. Among 120940 surgical operations a year, the mean incidence of postoperative DVT and PE was only 0.13 and 0.04 per cent respectively. No high-risk surgical group was identified. CONCLUSION: Venous thromboembolism is not as common in Chinese as in Caucasians, but it is certainly not rare. The majority of DVTs and PEs, however, were not associated with surgery, so routine thromboprophylaxis may not be required.     

Continuous measurement of oxygen consumption during cardiopulmonary bypass: description of the method and in vivo observations

BACKGROUND: Systemic oxygen consumption is not routinely measured during cardiopulmonary bypass, despite its potential benefits. We aimed to develop a noninvasive method to continuously measure oxygen consumption using respiratory mass spectrometry during hypothermic cardiopulmonary bypass in pigs. METHODS: Nine pigs weighing 18.5 (1.6) kg underwent hypothermic (32 degrees C) cardiopulmonary bypass for 180 minutes with 120 minutes of aortic cross clamping. An AMIS 2000 mass spectrometer (Innovision A/S, Odense, Denmark) was adapted for the on-line measurement of oxygen consumption by sampling the inlet and outlet gases of the membrane oxygenator together with measurement of the "expired" gas volume. RESULTS: Active cooling for 60 minutes reduced the venous blood temperature by 2.9 (0.8) degrees C and VO(2) by 0.70 (0.33) mL/kg/min. The 40-minute active rewarming restored the venous blood temperature by 4.4 (0.4) degrees C and oxygen consumption increased by 1.36 (0.33) mL/kg/min. There was wide interanimal variability, however, particularly at higher venous blood temperatures. Immediately after the release of aortic cross clamp, there was a noticeably acute increase in oxygen consumption in all the pigs (0.64 [0.21] mL/kg/min). CONCLUSIONS: A simple and safe adaptation of mass spectrometry allows continuous measurement of oxygen consumption during hypothermic cardiopulmonary bypass. The wide interindividual variations observed in this pilot study underscore the need to more accurately describe changes in oxygen consumption and how they are affected by temperature, oxygen delivery, and other interventions during cardiopulmonary bypass. As such, the technique may have an important role in clinical research and management of oxygen transport in patients undergoing cardiac surgery.     

Early Data from the First Population-Wide Breast Cancer-Specific Registry in Hong Kong

Background

Current measures for breast cancer prevention and options for treatment adopted in Hong Kong are mainly based on research data and clinical evidence from overseas. It is essential to establish a cancer-specific registry to monitor the status of breast cancer in Hong Kong.

Objectives

We summarized the current status of breast cancer in Hong Kong based on the data collected from Hong Kong Breast Cancer Registry (HKBCR).

Methods

Prevalent and newly diagnosed breast cancers (including in situ and invasive breast cancers) were registered in the HKBCR. Information on patient demographics, risk factors, medical information, and survival were analyzed and reported in this study.

Results

Data of 2,330 breast cancer patients were analyzed. We observed an earlier median age at diagnosis in Hong Kong than those reported in other countries. Distribution of cancer stage was: stage 0 (11.4%), stage I (31.4%), stage II (41%), stage III (12.5%), stage IV (0.8%), and unclassified (2.9%). The percentages of patients who received surgery, chemotherapy, radiation therapy, and endocrine therapy were 98.7, 67.9, 64.8, and 64.1%, respectively. At a median follow-up of 1.2?years, locoregional recurrence was recorded at 2%, distant recurrence at 2.8%, and breast-cancer–related mortality at 0.3%.

Conclusions

The HKBCR serves as a surveillance program to monitor disease and treatment patterns. It is pivotal to support research for more effective breast cancer prevention and treatment strategies in Hong Kong.     

Ethnic difference of clinical vertebral fracture risk

Summary

Vertebral fractures are the most common osteoporotic fractures. Data on the vertebral fracture risk in Asia remain sparse. This study observed that Hong Kong Chinese and Japanese populations have a less dramatic increase in hip fracture rates associated with age than Caucasians, but the vertebral fracture rates were higher, resulting in a high vertebral-to-hip fracture ratio. As a result, estimation of the absolute fracture risk for Asians may need to be readjusted for the higher clinical vertebral fracture rate.

Introduction

Vertebral fractures are the most common osteoporotic fractures. Data on the vertebral fracture risk in Asia remain sparse. The aim of this study was to report the incidence of clinical vertebral fractures among the Chinese and to compare the vertebral-to-hip fracture risk to other ethnic groups.

Methods

Four thousand, three hundred eighty-six community-dwelling Southern Chinese subjects (2,302 women and 1,810 men) aged 50 or above were recruited in the Hong Kong Osteoporosis Study since 1995. Baseline demographic characteristics and medical history were obtained. Subjects were followed annually for fracture outcomes with a structured questionnaire and verified by the computerized patient information system of the Hospital Authority of the Hong Kong Government. Only non-traumatic incident hip fractures and clinical vertebral fractures that received medical attention were included in the analysis. The incidence rates of clinical vertebral fractures and hip fractures were determined and compared to the published data of Swedish Caucasian and Japanese populations.

Results

The mean age at baseline was 62?±?8.2?years for women and 68?±?10.3?years for men. The average duration of follow-up was 4.0?±?2.8 (range, 1 to 14) years for a total of 14,733 person-years for the whole cohort. The incidence rate for vertebral fracture was 194/100,000 person-years in men and 508/100,000 person-years in women, respectively. For subjects above the age of 65, the clinical vertebral fracture and hip fracture rates were 299/100,000 and 332/100,000 person-years, respectively, in men, and 594/100,000 and 379/100,000 person-years, respectively, in women. Hong Kong Chinese and Japanese populations have a less dramatic increase in hip fracture rates associated with age than Caucasians. At the age of 65 or above, the hip fracture rates for Asian (Hong Kong Chinese and Japanese) men and women were less than half of that in Caucasians, but the vertebral fracture rate was higher in Asians, resulting in a high vertebral-to-hip fracture ratio.

Conclusions

The incidences of vertebral and hip fractures, as well as the vertebral-to-hip fracture ratios vary in Asians and Caucasians. Estimation of the absolute fracture risk for Asians may need to be readjusted for the higher clinical vertebral fracture rate.     

Interleukin-13 genetic polymorphisms in Singapore Chinese children correlate with long-term outcome of minimal-change disease.

BACKGROUND: Minimal-change nephrotic syndrome (MCNS) has been associated with atopy. As interleukin-13 (IL-13) has been implicated in the pathogenesis of MCNS, we postulated that IL-13 genetic polymorphisms could influence either susceptibility or clinical course of the disease. METHODS: Seventy-two Singapore Chinese children with MCNS and 78 normal controls were screened for single nucleotide polymorphisms (SNPs) in the IL-13 gene by direct sequencing. Allele and genotype frequencies of these SNPs were determined and their relationship with different clinical courses was analysed. RESULTS: Six SNPs were identified in the 5' promoter, exon 4 and 3' untranslated region (3'UTR). The three SNPs in the 3'UTR--4738 (G/A), 4793 (C/A) and 4926 (C/T)--were in tight linkage disequilibrium (Delta > or = 0.99). There was no difference in allele or genotype frequencies between MCNS children and normal controls. However, there was a significantly lower frequency of allele 4738G in those MCNS children who were still relapsing after 5 years of follow-up (G = 0.52), compared with those in complete remission (G = 0.72; P<0.05) and normal controls (G = 0.69; P<0.05). Haplotype analysis showed a significantly higher frequency of the GCC haplotype in controls and MCNS patients in complete remission (chi2 = 6.35; P<0.02), while the frequency of AAT haplotype was higher in those MCNS children still relapsing after 5 years of follow-up (chi2 = 5.38; P<0.02). Moreover, peripheral blood mononuclear cell IL-13 mRNA expression in patients with haplotype AAT was significantly higher than in those with haplotype GCC. CONCLUSIONS: These results suggest that genetic polymorphisms in the 3'UTR of the IL-13 gene correlate with long-term outcome of MCNS, rather than disease susceptibility, in Singapore Chinese children.